Installations are known for dispensing individual portions of milk on request from water and milk powder (French published patent specification No. 2 435 933), for dispensing lemonade from soda water and fruit juice (Belgian published patent specification No. 522 453), for dispensing fruit juice from water and fruit juice (British published patent specification No. 2 116 058) and for dispensing coffee from water and ground coffee.
Dispensing individual portions of flavored drinking yoghurt presents specific problems which are different from the problems presented for dispensing the above-mentioned drinks, and in particular because of the following reasons:
the installation must be capable of operating with materials of different viscosities since the various flavoring liquids are not all of the same viscosity, and yoghurt also has a different viscosity;
the installation must be capable of operating with portions of flavoring which vary from one flavoring to another; and
the installation must be capable of being cleaned automatically in a manner which is entirely reliable.
In addition, the installation must naturally be capable of properly preserving the foodstuffs used and of keeping them at top quality.